A Chinese man diagnosed with the country's first case of bird flu in more than a year has died in the southern city of Shenzhen.

The 39-year-old bus driver was admitted to hospital with pneumonia but tested positive for the H5N1 bird flu virus.

The strain has a high mortality rate, killing up to 60% of infected humans.

The man, surnamed Chen, developed a fever on 21 December and was admitted to hospital on Christmas Day. Local health officials said 120 people who had close contact with Chen have not developed any abnormal symptoms.

The Chinese health ministry has informed the World Health Organisation about the case, health officials added.

During the month prior to his fever, Chen, apparently had no direct contact with poultry and did not travel out of Shenzhen.

The city, home to 10 million people, is separated by a small river from Hong Kong, where 19,000 chickens have been slaughtered after two were confirmed last week to have died from the H5N1 virus.

Hong Kong also banned imports and sales of live poultry for three weeks after an infected chicken carcass was found at a wholesale market. Tests later confirmed that an Oriental magpie robin found dead on 17 December was also infected.

H5N1 rarely infects humans and usually only those who come into close contact with diseased poultry. China's last reported human case of H5N1 was in June 2010. A pregnant 22-year-old woman from central Hubei province died after being exposed to sick and dead poultry.